The fMRI signature of acute catatonic state and its response to benzodiazepines

We report for the first time, functional MRI markers of the acute retarded catatonic state and its response to benzodiazepines. In this cross-sectional MRI study, we have compared the resting state whole-brain, within-network and seed (left precentral gyrus)-to-voxel connectivity, as well as cortical complexity between a sample of patients in acute retarded catatonic state (n = 15) and a demographically-matched healthy control sample (n = 15). Additionally, we examined whether the above variables were different between responders (n = 9) and non-responders (n = 6) to lorazepam. Acute retarded catatonia was characterized by reduced functional connectivity, most robustly within the sensorimotor network, diffuse long-range hyperconnectivity, and seed-to-voxel hyperconnectivity in the frontoparietal and cerebellar regions. The lorazepam responders showed long-range as well as seed-to-voxel functional hyperconnectivity in comparison to the non-responders. Seed (left precentral gyrus)-to-voxel connectivity was positively correlated to the catatonia motor ratings. The catatonia sample showed reduced vertex-wise cortical complexity in the right insular cortex and contiguous areas. We have identified neuroimaging markers that characterize the acute retarded catatonic state and predict treatment response. We discuss how these novel findings have important translational implications for understanding the pathophysiology of catatonia and for predicting treatment response to benzodiazepines.